page {
	background-color: #383838;
}

.expression {
  color: #ccc;
  font-size: 2rem;
  word-break: break-all;
  letter-spacing:2px;
}

.result {
	color: #fff;
	font-size: 4rem;
	word-break: break-all;
}

.buttons-bg {
	background-color: #383838;
	display: grid;
	grid-template-columns: repeat(4, 1fr);
	grid-template-rows: repeat(5, 1fr);
	gap: 1px;
}

.buttons {
	background-color: #cfcfcd;
	display: flex;
	align-items: center;
	justify-content: center;
	font-size: 22px;
}

/* 合并单元格样式 */
.merged-cell {
	grid-column: 1 / 3;
	/* 从第1列合并到第2列 */
	background-color: #cfcfcd;
}

.operate {
	background-color: #fc9504;
}

.equal {
	background-color: #28a745;
}